Hole opener having interchangeable sleeve reamer

ABSTRACT

A hole opener for use in the Horizontal Directional Drilling (HDD) Industry is provided having an interchangeable sleeve reamer. The hole opener is in the form of a three-piece tool comprising a top shaft member, an interchangeable sleeve member and a bottom sub member, the interchangeable sleeve member being configured to be securely and removably mounted onto the top shaft member such that is does not rotate freely about the axis of the shaft member. In one embodiment, the bottom sub member also is interchangeable with other bottom sub members.

RELATED APPLICATION INFORMATION

[0001] This application claims the benefit of priority of U.S. provisional application Serial No. 60/260,266, filed in the United States Patent & Trademark Office on Jan. 9, 2001 in the names of Donald G. Morris, Sr. and David R. Morris, Sr.

FIELD OF INVENTION

[0002] The present invention relates to a hole opener having a replaceable and interchangeable sleeve reamer for use in the Horizontal Directional Drilling (HDD) industry. In particular, the present invention relates to a hole opener in the form of a three-piece tool comprising a top shaft member, an interchangeable sleeve member, and a bottom sub member. The interchangeable sleeve member is configured to be securely and removably mounted onto the top shaft member such that it does not freely rotate about the axis of the shaft member. The hole opener having the interchangeable sleeve reamer can be used to cut into dirt, clay, soft rock and hard rock by quickly and easily interchanging the sleeve member.

BACKGROUND OF THE INVENTION

[0003] The present invention is directed to a replaceable and interchangeable sleeve reamer for a hole opener for use in the Horizontal Directional Drilling (HDD) industry. The HDD industry generally pertains to the formation of holes for the laying of product, for example, water pipes, sewer lines, fiber optic cables, and the like. Included in the HDD industry are the River Crossing and Road Boring communities. In the HDD industry, the formation of the hole often requires the opening of a hole under a river bed or under existing roadway. When opening a hole under a river bed, existing roadway or other physical barrier, the hole is opened first at an certain angle to a desired depth, then continued horizontally to a desired distance and then back upward at a certain angle to an exit site. Typically, the hole is predrilled (i.e. pilot bored) by a one-piece drilling tool on a drill string, the drilling tool opening the hole first at the specific angle to the desired depth, then horizontally to the desired distance, then upwardly at a specific angle to the exit site. Once the hole is pilot-bored, the drilling tool is removed from the drill string and a hole opener is mounted on the drill string and pulled back through the hole with the drill string to open the hole to a larger diameter.

[0004] Typically, a hole is opened in several stages, the number of stages depending upon the size (i.e. diameter) required for the hole. Although the actual cutting ability of the reamer is one reason why several stages are required, the main reason is the ability of the fluid to remove the cuttings from and out of the hole. For example, to form a 16″ diameter hole, in the first stage, a 4¾″ hole is pilot bored; in the second stage an 8 or 9″ reamer is used to widen the hole; in the third stage, a 12 or 13″ reamer is used, and in the fourth stage, a 16″ reamer is used, fluid being used in each stage to remove additional cuttings from the hole.

[0005] In conventional practice, in each stage, a different hole opener is required to open the hole to a larger size. The typical hole opener currently used in HDD is a one-piece tool having a top shaft, a bottom sub and a reamer element. Therefore, after each stage, the existing hole opener must be removed from the drill string and a new hole opener capable of opening a larger diameter hole must be mounted to the drill string. This practice not only requires the purchase and use of several hole openers to complete one hole opening, it also significantly increases the amount of time necessary to open the hole since each existing hole opener must be removed from the drill string and a successive hole opener must be mounted on the drill string.

[0006] Drilling tools for use in oilfield applications have been developed which use interchangeable drill bits, reamer-stabilizers and other cutting tools. For example, U.S. Pat. No. 1,562,449 to Herrin, issued Nov. 24, 1925 and U.S. Pat. No. 2,506,795 to Koeln, issued May 9, 1950, disclose drilling tools for pre-drilling the initial pilot bore for a wellbore, each tool utilizing an arrangement of keys and slots to selectively prevent relative rotation between the parts thereon. However, neither drilling tool is adapted for opening the hole to the desired size by pulling back the tool and drill string. Rather, each of these drilling tools are lifted out of the well bore while the drill string remains intact and in the wellbore. U.S. Pat. No. 4,953,640 to Kurt, issued Sep. 4, 1990, discloses a quick detach bit apparatus for quickly changing drill bits on an oil field drilling tool for use in a wellbore. Kurt uses an arrangement of alternating splines and grooves provided on a drill bit for mating engagement with a corresponding arrangement provided on a chuck. The arrangement enables quick release of the drill bit and also prevents relative rotation between the bit and chuck.

[0007] Removable cutting elements for drilling implements in oil field applications also are known in the prior art. For example, U.S. Pat. No. 2,210,824 to Walker, Sr., issued Aug. 6, 1940, discloses a rotary drilling tool comprising a plurality of tool elements that are threaded over a portion of the tool body and are held captive between opposing locking collars. In U.S. Pat. No. 3,322,217 to De Orr Cook, issued May 30, 1967, a reaming tool is provided having a sleeve section that is threaded over a reduced diameter portion of a mandrel and held captive thereon by a section of drill pipe that is threaded onto the end of the mandrel. U.S. Pat. No. 4,549,613 to Case, issued Oct. 29, 1985, discloses a downhole tool for use as an oilfield tool, which utilizes a replaceable sleeve member. Case comprises two replaceable tool sleeve sections that are assembled about a drill stem. The sleeve sections are elongated cylindrical half sleeve sections which are mountable on and removable from a tool body.

[0008] None of these oil field drilling tools can be used in the HDD industry since the drill string remains in the wellbore and that they are not configured for all types of angled drilling and horizontal drilling. Further, the use of the term “reamer”, when used in reference to oil field applications, is meant to indicate a drilling tool which centralizes and stabilizes the drill hole. In the oil field application, once a pilot bore is drilled, a tool is mounted on the existing drill string and reams the pilot bore to ensure a perfect cylindrical hole; hence the term “reamer”. Thus, if a 8¾″ hole is pre-drilled, an 8¾″ reamer is mounted somewhere near the top of the drill string to keep it centered in the hole and to maintain the hole at 8¾″ diameter. In the oil field application, the reamer is not used to further open the hole to a larger diameter.

[0009] Accordingly, a need still exists for a hole opener having an interchangeable sleeve reamer. Such a hole opener should be configured such that an interchangeable sleeve reamer can be quickly and easily replaced with another interchangeable sleeve reamer. In addition, the interchanging of sleeve reamers should not require that the hole opener be removed from the drill string. Such a hole opener having an interchangeable sleeve reamer also should be capable of interchanging bottom sub members. Moreover, such a hole opener having an interchangeable sleeve reamer should be capable of opening a hole in successive stages and remove the cuttings or solids out of the hole in order to obtain a hole having the desired diameter.

SUMMARY OF THE INVENTION

[0010] Accordingly, it is an object of the present invention to provide a hole opener having an interchangeable sleeve reamer.

[0011] It is also an object of the present invention to provide a hole opener having an interchangeable sleeve reamer wherein the hole opener is configured such that an interchangeable sleeve reamer can be quickly and easily replaced with another interchangeable sleeve reamer.

[0012] It is another object of the present invention to provide a hole opener having an interchangeable sleeve reamer which does not required that the hole opener be removed from the drill string during the interchanging of sleeve reamers.

[0013] It is an additional object of the present invention to provide a hole opener having an interchangeable sleeve reamer which also includes an interchangeable bottom sub member.

[0014] It is a further object of the present invention to provide a hole opener having an interchangeable sleeve reamer which can open a hole in successive stages to obtain a hole having the desired diameter simply by the sequential replacement of an interchangeable sleeve reamer with an interchangeable sleeve reamer having a larger diameter.

[0015] It is yet another object of the present invention to provide a hole opener having an interchangeable sleeve reamer which can remove the cuttings or solids out of the hole during the opening of the hole.

[0016] Additional objects, advantages and novel features of the invention will be set forth in part of the description and claims which follows, and in part will become apparent to those skilled in the art upon examination of the following specification and claims or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be better understood with reference to the appended drawing sheets, wherein:

[0018]FIG. 1 is an exploded side perspective view of the hole opener having an interchangeable sleeve reamer of the present invention.

[0019]FIG. 2 is a cross-sectional view taken along the line A-A of the top shaft member of the hole opener of the present invention.

[0020]FIG. 3 is a bottom perspective view of the interchangeable sleeve reamer of the hole opener of the present invention.

[0021]FIG. 4 is a perspective view of a formed keyway slot and key member arrangement of the present invention.

[0022]FIG. 5 is a perspective view of an alternative embodiment of the hole opener having an interchangeable sleeve reamer of the present invention.

DETAILED DESCRIPTION

[0023] Referring to FIG. 1, the hole opener having an interchangeable sleeve reamer, generally designated 1, comprises a top shaft member 10, an interchangeable sleeve member 20 and a bottom sub member 30. As particularly shown in FIGS. 1 and 2, the top shaft member 10 comprises a externally threaded lower end 11, a distal second end 12, an elongated cylindrical body 13 and at least two external keyway half-slots 14 disposed longitudinally along a portion of the outer surface 15 of the elongated cylindrical body 13, each external keyway half-slot 14 having a lower end 16 proximal to lower end 11. Preferably, three external keyway half-slots 14 are spaced 120° apart about the outer circumference of the elongated cylindrical body 13 as shown in FIG. 2. In a preferred embodiment, each external keyway half-slot 14 is about one quarter inch (¼″) in depth and about five inches (5.0″) in length. However, it is to be understood that other dimensions of the keyway half-slots 14 are contemplated to be within the scope of the present invention.

[0024] Interchangeable sleeve member 20 comprises an upper end 21, a lower end 22, a body 23 and at least two internal keyway half-slots 24 as particularly shown in FIGS. 1 and 3. The internal keyway half-slots 24 are configured with the same dimensions as the corresponding external keyway half-slots 14. Each internal keyway half-slot 24 is disposed from the lower end 22 and longitudinally along a portion the internal surface 25 of body 23.

[0025] Preferably, three internal keyway half-slots 24 are spaced 120° apart about the inner circumference of the body 23 as shown in FIG. 3. In a preferred embodiment, each internal keyway half-slot 24 is about one quarter inch (¼″) in depth and about five inches (5.0″) in length. However, it is to be understood that other dimensions of the internal keyway half-slots 24 are contemplated to be within the scope of the present invention, provided that each internal keyway half-slot 24 is configured with the same dimensions as the dimensions of a corresponding external keyway slot 14.

[0026] The bottom sub member 30 comprises an internally threaded first end 31, an elongated cylindrical body 33 and a distal second end 32 as particularly shown in FIG. 1. Internally threaded first end 31 is configured to engage the externally threaded first end 11 of top shaft member 10. In this manner, top shaft member 10 and bottom sub member 30 can be removably secured to one another by threadingly engaging first ends 11 and 31.

[0027] In assembling the hole opener 1 of the present invention, the upper end 21 of the interchangeable sleeve member 20 is slidingly introduced over the lower end 11 of the top shaft member 10 and upwardly onto the elongated cylindrical body 13 such that the lower end 22 of the interchangeable sleeve member is parallel with the lower ends 16 of the external keyway half-slots 14. The interchangeable sleeve member is rotated about the top shaft until each external keyway half-slot 14 is aligned with a corresponding internal keyway half-slot 24, thereby forming at least two (2) keyway slots 44, as shown in FIG. 4. In the preferred embodiment, each keyway slot 44 is about one-half inch (½″) in width and about five inches (5″) in length. However, it is to be understood that other dimensions of the keyway slots 44 are contemplated to be within the scope of the present invention.

[0028] In order to prevent the interchangeable sleeve member from freely rotating about the axis of the top shaft 10, a key member 40 is inserted into each keyway slot 44. Each key member 40 comprises a first end 41 and a second end 42 and is dimensioned to have the same length and a slightly larger width than the keyway slot 44. Thus, in the preferred embodiment, each key member 40 is about five inches (5.0″) in length and slightly more than one-half inch (½″) in width. With this configuration, once second end 42 of the key member is introduced into the keyway slot 40, the first end 41 is tapped such that the entire length of the key member is snugly secured within the keyway slot 44. First end 41 can be provided with a tab or notch to facilitate removal of the key member from the keyway slot.

[0029] The keyway slot/key member arrangement enables the user to quickly and easily replace the interchangeable sleeve member 20 with another interchangeable sleeve member. Suitable interchangeable sleeve members include, for example, a Split Bit Reamer for dirt, soft and hard rock, a Wing Cutter for dirt and soft rock, and a Fly Cutter for dirt and soft rock. In this manner, the versatility of the hole opener with an interchangeable sleeve reamer provides numerous possibilities for utilizing the hole opener with other downhole devices.

[0030] Once the interchangeable sleeve member 20 is placed over the top shaft 10, the bottom sub member 30 is removably secured to the top shaft 10 by the threaded engagement of lower end 11 and first end 31. The bottom sub member 10 also can be interchanged other sub tools when different work in the hole is required. Suitable interchangeable bottom sub members include, for example, a Solid Sub to keep fluid passage stopped at the back of the reamer, a Pulling Eye Sub which hooks up to a Swivel to pull product (sewer line, optic cable) through the hole, a Barrel Reamer which swabs out the hole, and like sub members.

[0031] Referring again to FIG. 1, the top shaft member 10 is provided with a plurality of fluid holes 17 and interchangeable sleeve member 20 is provided with a plurality of fluid holes 27. Preferably the top shaft member 10 and interchangeable sleeve member 20 each have three fluid holes spaced 120° apart and which can be aligned along with the keyway half-slots. Thus, all such constructed interchangeable sleeve members can be interchangeable. These fluid holes 17 and 27 are for the passage of fluid such that cuttings and other solids can be removed from the hole.

[0032] Referring now to FIG. 5, an alternative embodiment for removably mounting the interchangeable sleeve member 120 over the top shaft member 110. In this embodiment, rather than the use of the keyway slot/key member arrangement to prevent the interchangeable sleeve member from rotating about the axis of the top shaft member, the top shaft member is provided with a plurality of apertures 114, preferably six apertures, about its circumference. The interchangeable sleeve member 120 is provided with a plurality of apertures 124, preferably six apertures, dimensioned with the same diameter as apertures 114. A rod or bolt member 140 is provided having a slightly larger diameter than the apertures 114 and 124. When the apertures 124 are aligned with the apertures 124, a bolt member 140 is tapped into and through aperture 114 and into aperture 124. Although this arrangement is meant to be an alternative means for removably mounting the interchangeable sleeve member to the top shaft member, it will be apparent to those skilled in the art that other arrangements can be utilized to enable the interchangeable sleeve member to be removably mounted over the top shaft member and that such other arrangements are considered to be within the scope of the present invention.

[0033] While particular embodiments of the invention have been described, it will be understood, of course, that the invention is not limited thereto, and that many obvious modifications and variations can be made, and that such modifications and variations are intended to fall within the scope of the appended claims. 

What is claimed is:
 1. A hole opener having an interchangeable sleeve reamer comprising (a) a top shaft member having an externally threaded lower end, a distal second end and an elongated cylindrical body joining said externally threaded lower end and said distal second end; (b) an interchangeable sleeve member having an open upper end, a distal open lower end and a body portion having a cylindrical opening therethrough connecting said open upper end and open lower end, and (c) a bottom sub member having an internally threaded first end, a distal second end and an elongated cylindrical body joining said internally threaded first end and said second distal end, said internally threaded first end being configured to engage said externally threaded lower end of said top shaft, thereby removably securing said top shaft member to said bottom sub member, wherein, said elongated cylindrical body of said top shaft member has an exterior surface upon which is disposed a first mating arrangement and wherein said cylindrical opening of said interchangeable sleeve member has a wall upon which is disposed a second mating arrangement which is configured to complement said first mating arrangement in such a manner that when said top shaft member is introduced within said cylindrical opening, said first and second mating arrangements can be aligned to form a cooperating arrangement which can be used to removably secure said interchangeable sleeve member onto said top shaft member.
 2. A hole opener having an interchangeable sleeve reamer in accordance with claim 1, wherein said first mating arrangement is at least two top keyway half-slots longitudinally disposed along the exterior surface of said top shaft member and said second mating arrangement is at least two sleeve keyway half-slots longitudinally disposed from said open lower end along the wall of said cylindrical opening, and wherein when each of said top keyway half-slots is aligned with a complementary sleeve keyway half-slot, complete keyway slots are formed.
 3. A hole opener having an interchangeable sleeve reamer in accordance with claim 2, further comprising a key member which is dimensioned to be introduced into one of said keyway slots and tightly fitted therein.
 4. A hole opener having an interchangeable sleeve reamer in accordance with claim 3, wherein a key member is provided for each of said complete keyway slots.
 5. A hole opener having an interchangeable sleeve reamer in accordance with claim 1, wherein said first mating arrangement is at least two top apertures disposed on the exterior surface of said top shaft member and said second mating arrangement is at least two sleeve openings disposed through said wall of said cylindrical opening and wherein when each of said top apertures can be aligned with a complementary sleeve opening.
 6. A hole opener having an interchangeable sleeve reamer in accordance with claim 1, further comprising a bolt member which is dimensioned to be introduced through one of said sleeve openings and into one of said top apertures and tightly fitted therein.
 7. A hole opener having an interchangeable sleeve reamer in accordance with claim 1, wherein said interchangeable sleeve member is selected from the group consisting of interchangeable sleeve reamers, split bit reamers, wing cutters and fly cutters.
 8. A hole opener having an interchangeable sleeve reamer in accordance with claim 1, wherein said bottom sub member is interchangeable with bottom sub members selected from the group consisting of solid subs, pulling eye subs and barrel reamer subs.
 9. A hole opener having an interchangeable sleeve reamer in accordance with claim 8, wherein said bottom sub is a solid sub member and said interchangeable sleeve member is an interchangeable sleeve reamer.
 10. A hole opener having an interchangeable sleeve reamer comprising: (a) a top shaft member having an externally threaded lower end, a distal second end, an elongated cylindrical body having an exterior surface, and at least two top keyway half-slots longitudinally disposed along said exterior surface, each of said two top keyway half-slots having a lower end; (b) an interchangeable sleeve member having an open upper end, a distal open lower end, a body portion having a cylindrical opening therethrough connecting said open upper end and open lower end, said cylindrical opening having a wall, and at least two sleeve keyway half-slots longitudinally disposed along said wall beginning at said open lower end, (c) a bottom sub member having an internally threaded first end, a distal second end and an elongated cylindrical body joining said internally threaded first end and said second distal end, said internally threaded first end being configured to engage said externally threaded lower end of said top shaft, thereby removably securing said top shaft member to said bottom sub member, wherein, said interchangeable sleeve member can be slidingly introduced over said top shaft member in such a manner that when said open lower end of said interchangeable sleeve member is aligned with said lower end of said top keyway half-slots, said top keyway half-slots can be aligned with said sleeve keyway half-slots to form complete keyway slots.
 11. A hole opener having an interchangeable sleeve reamer in accordance with claim 10, wherein said at least two top keyway half-slots are three top keyway half-slots spaced 120° apart about the outer circumferences of said elongated cylindrical body of said top shaft member and wherein said at least two sleeve keyway half-slots are three sleeve keyway half-slots spaced 120° apart about inner circumference of said wall of said cylindrical opening.
 12. A hole opener having an interchangeable sleeve reamer in accordance with claim 11, wherein when said three top keyway half-slots are aligned with said three sleeve keyway half-slots, three complete keyway slots are formed.
 13. A hole opener having an interchangeable sleeve reamer in accordance with claim 12, further comprising three key members, each of said key members being dimensioned to be tightly fitted within one of said keyway slots.
 14. A hole opener having an interchangeable sleeve reamer in accordance with claim 13, wherein each of said top keyway half-slots and said sleeve keyway half-slots is about five inches (5″) in length and about one-quarter inch (¼″) in depth, and wherein each of said key members is about five inches (5″) in length and slightly larger than one-half inch (½″) in width, thereby enabling said key members to be tightly fitted with respective keyway slots.
 15. A hole opener having an interchangeable sleeve reamer in accordance with claim 10, further comprising at least three fluid holes disposed within said top shaft member and at least three fluid holes disposed within said interchangeable sleeve member, wherein when said top and sleeve keyway half-slots are aligned, said fluids holes disposed within said top shaft member are aligned with said fluid holes disposed within said interchangeable sleeve member.
 16. A hole opener having an interchangeable sleeve reamer in accordance with claim 10, wherein said interchangeable sleeve member is selected from the group consisting of interchangeable sleeve reamers, split bit reamers, wing cutters and fly cutters.
 17. A hole opener having an interchangeable sleeve reamer in accordance with claim 10, wherein said bottom sub member is interchangeable with bottom sub members selected from the group consisting of solid subs, pulling eye subs and barrel reamer subs.
 18. A hole opener having an interchangeable sleeve reamer in accordance with claim 8, wherein said bottom sub is a solid sub member and said interchangeable sleeve member is an interchangeable sleeve reamer. 